QUICK-ACTION COUPLING FOR PIPES OR HOSES

Abstract: A quick-action coupling for pipes or hoses comprises a plastic housing (1) having at least one socket (2, 3) with a first socket part (4) lying at a distance from the insertion end (6) of the socket, for the essentially close-fitting accommodation of one end of a pipe or hose, a second socket part (5) connecting thereto and having a greater internal diameter than the first socket part. The second socket part (5), viewed from the first socket part towards the insertion end (6) of the socket, contains in succession a locking ring (7), a spacer ring (8), and a sealing ring (9). These rings are held in position by a retaining ring (10) which is disposed at the insertion end (6) of the socket and is connected to the housing (1). A metal reinforcing sleeve (11) is disposed around the outside of the second socket part (5), which reinforcing sleeve also secures the retaining ring in the axial direction.

Description: Quick-action coupling for pipes or hoses. The present invention relates to a quick-action coupling for pipes or hoses according to the preamble of claim 1. Such a quick-action coupling is known from British Patent No. 2,071,798. In the case of this known quick- action coupling the retaining ring has a J-shaped cross- section in the radial direction. The long part of the ring (long leg of the J) is threaded on the inside and screwed onto the outside of the also threaded socket part, while the short part of the retaining ring (short leg of the J) projects into the second socket part and in fact serves as a retaining ring. The known quick-action coupling has a number of disadvantages. Due to the fact that the retaining ring is screwed onto the outside of the socket, the diameter of the second socket part with the retaining ring screwed onto it is relatively great compared with the first socket part. Moreover, the retaining ring can be unscrewed from the socket relatively easily, which can have serious consequences in a situation in which high temperature and pressure prevail inside the coupling. Finally, in order to prevent the plastic socket from deforming under the influence of high temperature and pressure and the retaining ring from coming off the socket, or the socket creeping at higher temperatures at the position of the sealing ring, thus allowing leakage, the wall thickness of the socket and the retaining ring must be relatively great, with the result that the coupling becomes heavy, or the socket and the retaining ring have to be made of a high- grade plastic, thereby making the coupling relatively expensive. The object of the invention is to provide a coupling of the above entioned type which does not have the above disadvantages. This object is achieved by a quick-action coupling having the features listed in claim 1. The quick-action coupling according to the invention can be made from a conventional plastic (for example, polyethene or polybutene) and can still be made relatively slim, since the plastic parts of the coupling are enclosed in the metal reinforcing sleeve, with the result that the coupling can undergo little or no defor¬ mation in the axial and radial direction under the influence of high temperature and pressure. Preferred embodiments of the quick-action coupling according to the invention are described in the sub-claims. The invention will be explained in greater detail in the description which follows of a number of possible embodiments of a quick-action coupling according to the invention with reference to the appended drawing, in which: Fig. 1 is a longitudinal section of a quick-action coupling according to the invention, in the form of a right-angled bend; Fig. 2 is a longitudinal section of a quick-action coupling according to the invention, in the form of a straight connecting piece; Fig. 3 is a longitudinal section of a quick-action coupling according to the invention, in the form of a socket to be screwed onto a pipe end; Fig. 4 is a longitudinal section of a quick-action coupling of the type shown in Fig. 3, with a modified embodiment of the retaining ring; and Figs. 5 and 6 show two possible embodiments of a locking ring of a quick-action coupling according to the invention. The quick-action coupling according to the invention shown in Fig. l, in the form of a right-angled bend, comprises a plastic housing 1 with two sockets 2 and 3. Each socket comprises a first socket part 4 for the essentially close-fitting accommodation of an end (not shown) of a pipe or hose and a second socket part 5 connecting to the first socket part 4 and with a larger internal diameter than the first socket part 4. Viewed from the first socket part towards the insertion end 6 of the socket, the second socket part contains in succession a locking ring 7, a spacer ring 8, and a sealing ring 9. The locking ring 7 is shown only diagra matically here. The rings 7, 8 and 9 are held in place by a retaining ring 10 fitted at the insertion end 6 of the socket. The retaining ring 10 is situated inside the second socket part 5. A metal reinforcing sleeve 11 is disposed on the outside of the second socket part 5. This reinforcing sleeve 11, which can be made of, for example, aluminium, is flanged inwards at its one end 12 near the insertion end 6, thereby engaging around the retaining ring 10, and behind the end face 13 of the retaining ring 10 extending essentially in the radial direction. At its other end 14, the reinforcing ring 11 is also flanged inwards and thereby engages behind a radial shoulder 15 of the socket 2, 3 lying in the transition area between the first socket part 4 and the second socket part 5. In Fig. 1 the retaining rings 10 in the two sockets 2 and 3 are designed differently. In the retaining ring of the socket 2, at least two - and preferably four - short ribs 16, running in the peripheral direction and engaging in complementary open slots 17 in the wall of the second socket part 5, are provided on the outside. The retaining ring 10 in the socket 3 is provided on the outside with two ribs 18, 19, running over the entire periphery and engaging in complementary grooves 20, 21 on the inside of the second socket part 5. Due to the fact that the ribs 16, 18, 19 engage in the slots 17 or grooves 20, 21 of the second socket part 5, the retaining ring 10 can be positioned well during the fitting. The quick-action coupling according to the invention shown in Fig. 2 is in the form of a straight connecting piece with two sockets 22 and 23. The design of the sockets 22 and 23 differs from that of the sockets 2 and 3 in Fig. 1 in that the shape of the retaining rings 24 is different. Each retaining ring 24 is provided on the outer periphery with an essentially radial shoulder 25 which rests against the end face 26 of the second socket part 5. The part of the retaining ring 24 situated inside the second socket part 5 is not provided with ribs. The positioning of the retaining ring 24 relative to the second socket part 5 during fitting is achieved by means of the radial shoulder 25. Figs. 3 and 4 show quick-action couplings according to the invention of the type which can be screwed onto a pipe end (not shown here) by means of screw thread 27. ' These couplings " have only one socket. The retaining ring 28 of the quick-action coupling of Fig. 3 is provided on the outer periphery with a peripheral rib 29, which engages in a complementary groove on the inside of the second socket part 5, and an essentially radial shoulder 30 behind which the inward flanged end 12 of the reinforcing sleeve 11 engages. The retaining ring 28 is also provided with a preferably flexible extension piece 31 extending in the axial direction from the radial shoulder 30, which piece supports the inserted pipe or hose end when it is being bent, so that stress concentrations in the pipe or hose are prevented. The design of the socket of the quick-action coupling shown in Fig. 4 corresponds entirely to the design of the socket 3 of the quick-action coupling shown in Fig. 1. In the case of all embodiments of the quick-action coupling according to the invention, the internal diameter of the retaining ring 10, 24, 28 is essentially the same as the internal diameter of the first socket part 4. The inside of the retaining ring serves as a guide for a pipe or hose end to be inserted. Figures 5 and 6 show two possible embodiments of the locking ring 7 of the quick-action coupling according to the invention. The inward slanting part 32 of the locking rings 7 consists of a number of lips or teeth 33 which are slightly flexible. These lips or teeth 33 are bent outwards slightly during the insertion of a pipe or hose end. During withdrawal of the pipe or hose end, the lips or teeth 33 engage in the outside wall of the pipe or hose and thereby ensure that the pipe or hose cannot be pulled out any further. In order to make it still possible for the inserted pipe or hose end to be removed from the coupling again, the teeth or lips 33 are made saw-toothed in the known manner, so that they form a sort of "screw thread" on engagement in the pipe or hose. The inserted pipe or hose can be "screwed" out of the coupling by turning the inserted pipe or hose. In order to prevent the locking ring 7 from turning with the inserted pipe or hose end while it is being unscrewed, the locking ring 7 can be provided with a number of flexible lips, running in the same tangential direction and, depending on the type of locking ring, projecting axially or radially at an angle from the external surface of the locking ring. These flexible lips are indicated by 34 in Fig. 5 and by 35 in Fig. 6. In the case of the locking ring 7 shown in Fig. 5, the flexible lips 34 are disposed on the end face 36 of the locking ring 7 facing the first socket part 5-. In the embodiment of the locking ring 7 shown in Fig. 6, the flexible lips 35 are disposed on the outer periphery of the locking ring 7. The free end of a flexible lip 34, 35 can knock against a projection disposed in the second socket part 5 when an inserted pipe or hose end is being unscrewed from a socket, with the result that further turning of the locking ring is prevented. Such a projection is indicated by 39 in Fig. 3. If there is a projection 39, the locking ring 7 must be of the type shown in Fig. 5. When a locking ring 7 of the type shown in Fig. 6 is used, the projection must be disposed at the position of the locking ring on the inside wall of the second socket part 5. A locking ring 7 of the type shown here, having flexible lips 34, 35 disposed on the outside, can be used not only in the quick-action coupling according to the invention described above, but also in other types of quick-action couplings in which a locking ring is provided. For manufacturing reasons, the locking ring may be made up of several coaxial partial rings. The invention is not limited to the embodiments of the quick-action coupling according to the invention described above and shown in the drawing. Other embodiments are possible within the scope of the invention. For example, the retaining ring can be a different shape, while the reinforcing sleeve 11 can also be designed differently, for example without inward flanged end at the position of the transition between the first and second socket part. The locking ring can also be in a different form.

Claims: Cla ims 1. Quick-action coupling for pipes or hoses, com¬ prising a plastic housing (1) , having at least one socket (2, 3;22 , 23) with a first socket part (4) lying at a distance from the insertion end of the socket, for the essentially close-fitting accommodation of one end of a pipe or hose, a second socket part (5) connecting thereto and having a greater internal diameter than the first socket part, which second socket part, viewed from the first socket part towards the insertion end of the socket, contains in succession a locking ring (7) , a spacer ring (8) , and a sealing ring (9) , which rings are held in position by a retaining ring (10;24;28) which is disposed at the insertion end of the socket and is connected to the housing, characterized in that the retaining ring (10) is situated essentially inside the second socket part (5) , and in that a reinforcing sleeve (11) is disposed around the outside of the second socket part, which reinforcing sleeve (11) is flanged inwards at its one end (12) near the insertion end of the socket, thereby engaging around the retaining ring (10) , and at its other end (14) is also flanged inwards and thereby engages behind an essentially radial shoulder (15) of the socket lying in the transition area between the first (4) and second socket part (5) . 2. Quick-action coupling according to claim 1, characterized in that the retaining ring (10) is provided on the outside with ribs (16;18, 19) running in the peripheral direction and engaging in complementary grooves (17;20,21) on the inside of the second socket part (5). 3. Quick-action coupling according to claim 1, characterized in that the retaining ring (24) is provided on the outer periphery with an essentially radial shoulder (25) which rests against the end face (26) of the second socket part (5) . 4. Quick-action coupling according to claim 1, characterized in that the retaining ring (28) is provided on the outer periphery with an essentially radial shoulder (30) behind which the one inward flanged end (12) of the reinforcing sleeve (11) engages, and in that the retaining ring (28) is also provided with an extension piece (31) extending axially from the radial shoulder (30) . 5. Quick-action coupling according to one or more of claims 1 - 4, characterized in that the reinforcing sleeve (11) is made of metal, preferably aluminium. 6. Quick-action coupling according to one or more of claims 1 - 5, characterized in tha't the locking ring (7) is provided with a number of flexible lips (34;35), running in the same tangential direction and projecting axially or radially at an angle from the external surface of the locking ring, the free end of which lips can butt against a projection (39) disposed at the position of the locking ring in the second socket part (5) . 7. Quick-action coupling according to claim 6, characterized in that the flexible lips (35) are disposed on the outer periphery of the locking ring (7) . 8. Quick-action coupling according to claim 6, characterized in that the flexible lips (34) are disposed on an end face (36) of the locking ring (7) facing the first socket part (4) . 9. Quick-action coupling according to one of claims 6 - 8, characterized in that the locking ring (7) is made up of several coaxial partial rings.

Inventors: LODDER BERNHARD, VAN DIJK BEREND JAN, VAN DONGEREN JAN PETER, LODDER, BERNHARD, VAN DIJK, BEREND, JAN, VAN DONGEREN, JAN, PETER
Applicants: DIJK BEREND JAN VAN, DONGEREN JAN PETER VAN, LODDER BERNHARD, WAVIN BV, LODDER, BERNHARD, VAN DIJK, BEREND, JAN, VAN DONGEREN, JAN, PETER, WAVIN B.V.
Application year: 1994
Main classification: F16L37
IPC codes: F16L37